Stair elevator for invalids



Oct. 4, 1955 e. P. SCOTT STAIR ELEVATOR FOR INVALIDS 2 Sheets-Sheet 1Filed Nov. 17, 1952 'IIIIIIIIIIIIIII IIIIIII A A TTORNEVS.

Oct. 4, 1955 G. P. SCOTT STAIR ELEVATOR FOR INVALIDS 2 Sheets-Sheet 2Filed NOV- 17, 195 2 INVENTOR.

A TTORNE YS.

United States Patent STA-IR ELEV ATBR FOR INVA L'IBS George -P.Scott,.Jackson,1Mo.

Application November 17, I952, Serial'No. 320,899

4 Claims. .(Cl. l8714) This invention relates 'to elevators for carryingpersons up and down -a stairway and has for its principal object toprovide a small self-contained, lightweight unit that is readily mountedalong oneside of a stairway and which leaves ample room for persons touse the stairway in a regular way. I

Other objects of the invention are to provide a stair elevator employinga monorail to whichza'll of the parts including a traveling chair areattached, to provide the elevator with simple and effective automaticsafety controls, and to provide an elevator .in which movement of thechair is under control of the rider.

In accomplishing these and other objects .of the invention hereinafterpointed out, I have provided an improved structure, the preferred formof which is illustrated in the accompanying drawings, wherein:

Fig. l is a perspective view of a stairway equipped with an elevatorembodying the .features of the present invention.

Fig. 2 is a partial longitudinal section to illustrate mounting of thechair on the monorail.

Fig. 3 is a partial front view of the elevator showing the chair inpartial section.

Fig. 4 is a horizontal section through the chair illustrating attachmentof the cable through an automatic brake control lever.

Fig. 5 is a partial longitudinal section through the stair showing therail and chair 'in elevation.

Fig. 6 is a fragmentary section .on :the line .of Fig.2.

Fig. 7 is a side elevational view of the rail and chair as viewed fromthe Wall side at the upper end .of the stair.

Fig. 8 is a section through the track .and chair truck on the line 88 ofFig. 6.

Fig. 9 is a diagram of the electric circuit supplying the motor andcontrol circuit.

Referring more in detail .to the drawings:

1 designates an ordinary stairway comprising .a series of steps 2composed of risers .3 and -treads.4 whereon a person may climb from alower floor 5 to an .upper floor or landing 6.

Mounted on the stairway .at .one side .thereof .is an invalids elevator7 constructed in accordance with the present invention. The elevatorcomprises .a-self-contained unit including a track or ,rail 8, .acarriage .or .chair 9, and the operating mechanisms therefor.

The track 8 is of monorail type in .that it is a single I-beam having avertical web 11 and .upper and lower flanges 12 and 13. The rail is of;alength to extend .trom the floorS along the length of the stairway .and.to project over the upper floor 'or landing 6 for accommodating :thechair 9 at the respective'ends of the rail. The :chair may thus be movedfrom a position zfibOllt the .height of a chair, forwardly of the lowerstep, to a similar position over the upper floor or landing 6. The railis supported from the treads 4 by means .of stands ;or brackets .14:thatthe upper flange 12 of the rail.

"2 are attached to the underside of the flange .13 and to the treads 4.The brackets 14 are arranged at suitable intervals along the rail so asto firmly support the rail .and retain the chair in stable positionduring its movement up and down the rail as later described.

Mounted at the upper end of the rail and preferably carried by the upperends of the brackets 14 is amotor 15 having a self-contained speedreduction unit, indicated -by the housing 16, for driving a reel orwinding drum 17 that extends across the end of the rail with the upperperiphery of the spool portion 18 slightly above The reel or windingdrum 17 also has end flanges 19 and 20 to retain ,a cable 21 thatconnects the winding drum with the chair-9.

The chair 9 includes spaced side platesor frames .22-and 23 of generallytriangular shape with their long edges 24 extending parallel with thesides-of the track and attached to lateral flanges 25 and 26 of anglemembers 27 and 28. The other flanges 29 and 30 of the angle members pro-Zject downwardlygat the sides of the rail and carry front and rear pairsof wheels .or rollers 32 and 33, the rollers being mounted on studs .34that are carried by the depending flanges of the angles near the .ends'thereof. The

between the interior surfaces of the rail flanges so that theperipheries may roll upon the faces 35 and 3.6 .ofthe respective flangesas best shown in Fig. 6.

'The peripheries of the rollers are conical to conform with theangularity of the respective flanges to support the cha'irin stableposition on therail. The forwardedges 3710f the side plates 22 and 23are connected by .a front plate '38 carrying a forwardly projecting footrest .39. Mounted on the upper edges 40 of the side and front plates isa.seat 41 having an arm and back rest 42 and 43.

The seat,.,front, and side plates thus form a housing for enclosing aspring tensioned reel 44 for winding up and paying out-an electricalcable 45 which contains electrical conductors that connect the motorcircuit with a controller switch 46. The controller 46 is mounted undera ,proiecting edge of .the seat 41 and .is operated by a lever 47.

Extending across the flanges 26 and .27 above the @up ,per flange of therail .are spaced transverse members 48 and 49. The member 48 carries .apulley 50 that is journalled thereon by a stud 51. The cable 2-1 passeswithin a circumferential groove of the pulley 50 and the end thereof isconnected with a .lever.53 of .a-brake mechanism 54. The brake mechanismincludes an eccentric that operates in a slot 56 of the side plate 23 so.that the periphery .57 of the eccentric is in position .to vengageagainst the web 11.0fthe rail. The eccentric 55 is carried on ashaft 57that is journalled within the flange 25 of. the angle '27, the arm .53being rigidly .connected with the upper-end of the shaft. The arm 53 isnormally retained in contact With-. a v.microswitch 58 that is alsomounted on the flange 25 .asibest shown in Fig. 4. With thisarrangement, the tension or pull on the .cable keeps the eccentric outof contact with the web of the rail.

However, should the cable break or .become slack, 'the eccentricautomatically sets .to .grip the web of the rail by means .Qfacoilspring 59 having .one end attached to the fleverand the otherendattached to an ear 60 on the flange 25.

Carried at the front and rear of the chair above the upper flange of therail are limit switches-61 and .62 having .operating levers '63 and 264for respectively engaging lugs 65 and 66 at the respective lower andupper ends of the :rail as shown in Fig. 1. Mounted on the carriage 'and'iIlTPOSitiOD. to engage a lug or arm -67 at the upper end of :the rail:is .a lever 68. The lever 68 is best shown in Fig. 4. It is pivotedatone end to the chair as indicated rollers are of a diametercorresponding with the spacing at 69. The other end of the lever isyieldingly retained in spaced relation with the chair by a coil spring70 that has one end engaging against the chair and the other end againstthe lever as shown in Fig. 4. Mounted on the upwardly extending lug orarm 67 is a switch 72 adapted to be engaged by the lever 68 in case offailure of the upper limit switch.

The cable 45 contains conductors 73, 74 and 75 that connect the limitswitches 62 and 63, controller 46, and switch 53 in circuit with themotor 15 and with a supply circuit including conductors 76 and 77 thatare adapted to be connected by a plug 78 with any convenient electricalsocket. The safety switch 72 is connected into the main circuit as shownin Fig. 9.

Assuming that the elevator is assembled as a self-contained unit andinstalled on a stairway as above described, with the chair at the lowerend of the track, the operator seats himself on the seat 41 of the chair9 and moves his feet to the platform 39. He then manipulates thecontroller 46 to energize the motor 15 through the conductors 74 and 73and limit switch 62. The motor then begins to operate and rotates thewinding drum 17 to reel the cable 21 thereon and draw the chair up thetrack to the top of the stairs. The chair rolls along the rail with thewheels bearing against the tapered faces of the flanges l2 and 13, whichtogether with the web 11, holds the chair in stable position on therail. When the chair reaches the top of the stairs, the lever 64 of thelimit switch 62 engages the lug 66 to automatically open the motorcircuit and stop movement of the carriage. The chair will then remain atthe top of the stairs until the person desires to descend to the firstfloor. With the limit switch 62 open and the switch 63 closed, the motorwill rotate in reverse direction and cause the winding of the drum topay out the cable and permit descent of the chair on the rail until thearm 63 of the limit switch 61 engages a lug 65 thereby interrupting thecircuit to the motor and stopping movement of the chair.

Should the cable break or become slack for any reason, the spring 5%becomes effective to swing the arm 53 away from the microswitch 58 andopen circuit between the controller and the motor and at the same timeset the brake mechanism in gripping engagement of the web 11 so that thechair is prevented from a runaway descent to the lower end of the track.When the cable is repaired, the tension of the chair, acting inopposition to the spring 59, again brings the arm 53 into position forreleasing the eccentric from its gripping contact with the rail and forclosing the switch 58. The circuits are then in condition so that thechair may be operated upon manipulation of the controller 46. Should theupper limit switch fail to operate, the lever 68 will engage the safetyswitch 72 and stop operation of the motor. Should this happen, operationis reestablished by pressing the switch lever 68 in the direction of thechair to release the microswitch. The switch 62 is also important toprevent possible injury to the rider and damage to the equipment in casethe rider should suddenly move the control lever through neutral toreverse position. When this happens, operation stops, but as soon as thespring pressed lever strikes the switch 58, the switch opens the circuitas above described.

From the foregoing it is obvious that I have provided an elevator forinvalids which consists of a self-contained, light-weight unit that iseasily installed on a conventional stair and which may be readilyremoved when desired since no alteration is required in either the stairor the building. It is also obvious that I have provided the elevatorwith simple and eflicient safety control mechanisms to stop the chair inany position along the length of the track in case of failure of thecable or any part of the power mechanism. It is also obvious that I haveprovided a safety stop for automatically stopping movement of thecarriage at the upper end of the rail in case the upper limit switchshould fail to operate or should the operator become excited andimproperly operate the control lever.

I claim:

1. A stair elevator including, a monorail adapted for support on a stairand having a web and upper and lower flanges extending laterally fromthe web, a power unit, a chair having side supports provided withportions depending on opposite sides of the monorail, wheels carried bysaid depending portions of the side supports and having peripheralportions adapted for rolling contact with said upper and lower flangesand having face portions closely adjacent side faces of said webportion, a brake carried on the depending portion of one of said sidesupports of the chair, a spring for exerting pressure on the brake inthe direction of the web portion of the monorail to draw the dependingportion of the opposite chair support toward the monorail to effectengagement of one of said portions at that side of the monorail withsaid monorail for cooperating with the brake in gripping the monorailtherebetween, means connecting the power means with the chair throughsaid brake for normally holding the brake out of pressure exertingposition for free movement of the chair up and down the monorail uponactuation of the power unit and for tensioning said spring whereby thespring acts to urge the brake into said pressure exerting position incase of failure of said connecting means for stopping movement of thechair on said monorail.

2. A stair elevator including, a monorail adapted for support on a stairwith an upper end thereof at a top of the stair and a lower end at abottom of the stair, said monorail having a web and upper and lowerflanges extending laterally from the web, a power unit carried by theupper end of the monorail and having a winding drum, a chair having sidemembers provided with portions depending on opposite sides of themonorail, wheels carried by said depending portions of the side membersand having peripheral portions adapted for rolling contact with saidupper and lower flanges and having face portions closely adjacent sidefaces of said Web, brake means carried on the depending portion of oneof said side members of the chair, a spring for exerting pressure on thebrake means in the direction of the web of the monorail to draw theopposite side member toward the monorail to effect movement of one ofsaid portions at that side of the monorail into contact with themonorail forcooperating with the brake means in respectively grippingopposite sides of the monorail, a cable having one end wound on thewinding drum and the other end connected with the chair through saidbrake means for normally holding the brake means out of pressureexerting position for free movement of the chair up and down themonorail upon actuation of the power unit and for tensioning said springwhereby the spring is effective to urge the brake into said pressureexerting position in case of failure of the cable and its connectionsfor stopping movement of the chair on said monorail.

3. A stair elevator including, a monorail adapted for support on a stairand having an upper end at a top of the stair and a lower end at abottom of the stair, said monorail having a web portion and upper andlower flange portions extending laterally from the web portion, a powerunit carried by the upper end of the monorail and having a laterallyprojecting winding drum extending transversely of the upper end of themonorail, a chair having side supports provided with flanges dependingon opposite sides of the monorail, wheels carried by said flanges andhaving rolling contact with said upper and lower flanges, a brakecarried on the flange of one of said side supports of the chair, aspring for exerting pressure of the brake in a direction to effectgripping of the monorail, a cable having one end wound on the windingdrum and the other end connected with the chair through said brake fornormally holding the brake out of pressure exerting position for freemovement of the chair up and down the monorail upon actuation of thepower unit and for tensioning said spring whereby the spring acts tourge the brake into said pressure exerting position in case of failureof the cable and its connections to stop movement of the chair on saidmonorail.

4. A stair elevator including, a monorail adapted for support on a stairand having an upper end at a top of the stair and a lower end at abottom of the stair, said monorail having a web portion and upper andlower flange portions extending laterally from the web portion, a powerunit carried by the upper end of the monorail and having a laterallyprojecting winding drum extending transversely of the upper end of themonorail, a chair having side plates on opposite sides of the monorail,angles having flanges fixed to the side plates and flanges depending onrespective sides of the monorail, wheels carried by said dependingflanges and having rolling contact with said upper and lower flanges, ashaft extending through one of the flanges that is fixed to one of theside plates, a brake on the shaft, a lever arm on the shaft, a springconnected with the lever arm for applying the brake to the monorail todraw the depending flange at the opposite side of the monorail to eifectgripping of the monorail, a pulley on said chair, a cable having one endwound on the winding drum and the other end connected with the lever armto connect the chair with the power unit and for normally holding thebrake against action of the spring for free movement of the chair up anddown the monorail upon actuation of the power unit whereby the 10 springacts to urge the brake into said pressure exerting position in case offailure of the cable and its connections to stop movement of the chairon said monorail.

References Cited in the file of this patent 15 UNITED STATES PATENTS643,674 Muirhead Feb. 20, 1900 1,358,062 Davis Nov. 9, 1920 1,768,650Wood July 1, 1930 20 2,507,887 Cheney May 16, 1950

